In "A Nightmare on Face Time", the boys intended to go to the Monster Mash, hoping to enter a costume contest. This was thwarted when they walked in on the 'Redbox Killers' robbing a Redbox vending machine in a local Kum & Go.
After Kyle Broflovski's iPad is recovered, the Park County Police Force decided to send one of their own to the Monster Mash, with Stan Marsh on Face Time. In disguise as Gangnam-stein, the police officer and Stan began to search for the Redbox Killers, but are thwarted when Randy Marsh assumes control over Stan's iPad.
Randy, in a dazed rage, proceeds to crash the event and proceeds to rampage throughout town, terrorizing those who stream movies. After chasing Filmore Anderson and his friend out of their bedroom, and out the front door, the police officer controlling the Gangnam-stein costume is shot, and killed.